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J Cynamon

Publications and source records attributed to J Cynamon.

At least 37 records · Page 2Linked to original sources
PubMed1997

Imaging of the vascular system for endovascular grafting and other procedures.

Success of endovascular therapy largely depends on accurate imaging before, during, and after the procedure. The vascular system can be evaluated noninvasively with computed tomography (CT), magnetic resonance (MR) imaging, and duplex ultrasound (US), or invasively with angiography and intravascular ultrasonography (IVUS). Noninvasive methods are preferred for both preprocedure screening and postprocedure follow-up, whereas invasive imaging modalities constitute an essential part of the endovascular procedure. Invasive techniques are also used in preprocedural or postprocedural evaluation when noninvasive methods are unable to obtain important diagnostic information, or when the confirmation of noninvasive imaging findings is desired. Specific roles of these modalities for endovascular treatment of aortoiliac aneurysms are discussed.

Angiography↗
PubMed1997

Varying strategies and devices for endovascular repair of abdominal aortic aneurysms.

The endovascular repair of abdominal aortic aneurysms has been investigated in a clinical setting since 1991. Although initially the procedure was performed using surgeon-made devices, it did not take long for the medical industry to realize the potential of this procedure. There are six commercially made devices, which are unique, each with their own strengths and weaknesses. This article describes the principal endovascular graft types that are currently under investigation as well as the strategies for their use. In addition, the inclusion criteria for endovascular repair of abdominal aortic aneurysms are discussed.

Aortic Aneurysm, Abdominal↗
PubMed1997

Endovascular approaches for traumatic arterial lesions.

Vascular injuries caused by blunt or penetrating trauma can be challenging to diagnose and treat, particularly when they involve central vessels. Endovascular treatment for vascular trauma includes the placement of embolization coils and intravascular stents and the employment of stented grafts. The use of stented grafts appears to be associated with decreased blood loss, a less invasive insertion procedure, reduced requirements for anesthesia, and a limited need for an extensive dissection in a traumatized field. These advantages are especially important in patients with central arteriovenous fistulas or false aneurysms, particularly those who are critically ill from other coexisting injuries or medical comorbidities. In these circumstances, the use of stented grafts already appears justified to treat traumatic central arterial lesions. Endovascular grafts are important tools for the treatment of vascular trauma, and they should be included in the armamentarium of the vascular surgeon.

Angiography↗
PubMed1997

Endovascular grafting for aortoiliac occlusive disease.

Aortoiliac occlusive disease is a significant cause of lower extremity ischemic symptoms. Over the past two decades, most patients have been treated with a variety of surgical procedures, including aortofemoral and extra-anatomic bypasses. Most recently, percutaneous balloon angioplasty and stents have been successfully used for the treatment of limited iliac lesions. New endovascular grafts that combine vascular grafts with stents in a device with new characteristics may allow the successful treatment of patients with extensive aortoiliac occlusive disease in a less invasive fashion. In our early experience, the endovascular grafts were constructed with Palmaz balloon-expandable stents and standard polytetrafluoroethylene (PTFE) grafts. The 18-month primary and secondary patency rates were 89% and 100%, respectively, with a limb salvage rate of 94%. Endovascular grafts can be successfully used to treat patients with extensive aortoiliac occlusive disease, with excellent early results. Long-term results and further graft improvements will define their role in the treatment of patients with aortoiliac occlusive disease.

Aorta, Abdominal↗
PubMed1996

Endoluminal therapy with endovascular grafts.

The addition of balloon-expandable stents to conventional graft material allows minimally invasive repair of aortic and other aneurysms, arterial occlusions, and arterial trauma. Vascular access can be made at a site far from the pathology.

Aneurysm↗
PubMed1996

Endovascular aortounifemoral grafts and femorofemoral bypass for bilateral limb-threatening ischemia.

PURPOSE: Although axillobifemoral bypass procedures have a lower mortality rate than aortobifemoral bypass procedures, they are limited by decreased patency, moderate hemodynamic improvement, and the need for general anesthesia. This report describes an alternative approach to bilateral aortoiliac occlusive disease using unilateral endovascular aortofemoral bypass procedures in combination with standard femorofemoral reconstructions. METHODS: Seven patients who had bilateral critical ischemia and tissue necrosis in association with severe comorbid medical illnesses underwent implantation of unilateral aortofemoral endovascular grafts, which were inserted into predilated, recanalized iliac arteries. The proximal end of the endovascular graft was fixed to the distal aorta or common iliac artery with a Palmaz stent. The distal end of the graft was suture-anastomosed to the ipsilateral patent outflow vessel, and a femorofemoral bypass procedure was then performed. RESULTS: All endovascular grafts were successfully inserted through five occluded and two diffusely stenotic iliac arteries under either local (1), epidural (5), or general anesthesia (1). The mean thigh pulse volume recording amplitudes increased from 9 +/- 3 mm to 30 +/- 7 mm and from 6 +/- 2 mm to 26 +/- 4 mm ipsilateral and contralateral to the aortofemoral graft insertion, respectively. In all cases the symptoms completely resolved. Procedural complications were limited to one local wound hematoma. No graft thromboses occurred during follow-up to 28 months (mean, 17 months). CONCLUSIONS: Endovascular iliac grafts in combination with standard femorofemoral bypass grafts may be an effective alternative to axillobifemoral bypass in high-risk patients who have diffuse aortoiliac occlusive disease, particularly when bilateral axillary-subclavian disease is present.

Aged↗
PubMed1996

Use of a water enema to facilitate localization of gastrointestinal hemorrhage during Tc-99m labeled RBC scintigraphy.

The authors report the use of a tap water enema to displace, and thereby localize, a site of colonic bleeding that had remained fixed in the left lower quadrant of the abdomen and could not be accurately localized. In similar cases, this maneuver may help to localize colonic bleeds in a timely fashion, avoiding protracted imaging and obviating the need for additional diagnostic testing.

Aged↗
PubMed1996

Infrapopliteal percutaneous transluminal angioplasty: what we know.

We believe that a substantial experience demonstrating the effectiveness and safety of infrapopliteal artery PTA has been accumulated. It is clear that the results of tibial PTA and femoropopliteal PTA are closely associated for most patients undergoing limb salvage procedures. Anatomic selection is most important; patients with focal disease and restorable runoff will generally benefit, and interventional radiologists should concentrate on treating this group of patients. PTA and surgery for limb salvage patients are indeed complementary procedures, and patients will benefit most by a methodical team approach to treatment. Problems with reporting of data in the literature have obscured the true effectiveness of distal PTA, with such deficiencies leading to both overestimation and underestimation of clinical utility. Nevertheless, the preponderance of evidence (as we see it) suggests a clinical effectiveness of about 80% at 2 years in appropriately selected patients. Like Dr. Fraser and his co-authors, we would welcome randomized trials of tibial PTA versus surgery, but even in the absence of these, the reporting of indications and results needs to be standardized: severity of symptoms at presentation and the extent of conservative treatments employed before intervention; life-table methodology on an intent-to-treat basis with clear delineation of end points; stratification by important variables such as lesion length, runoff status, extent of preexisting tissue loss, presence of diabetes and ESRD, and ideally, functional outcome and quality-of-life measures. Finally, we should learn from our surgical colleagues that close surveillance and early reintervention will probably increase the effectiveness of our percutaneous treatment methods.

Angioplasty, Balloon↗
PubMed1995

Placement of endovascular stented grafts via remote access sites: a new approach to the treatment of failed aortoiliofemoral reconstructions.

Endovascular grafting is a technique that combines the use of intravascular stents and prosthetic grafts to fabricate devices with unique properties. The purpose of this study is to describe the use of endovascular graft technology in the treatment of failed or failing standard aortoiliofemoral reconstructions. Over a 15-month period five patients with limb-threatening ischemia and failed aortofemoral or iliofemoral reconstructions underwent successful placement of six endovascular grafts to revascularize seven severely ischemic lower extremities. Standard thin-walled 6 mm polytetrafluoroethylene grafts and Palmaz balloon-expandable stents were used to fashion each reconstruction. In addition to the primary endovascular grafts, three patients underwent immediate femoropopliteal bypasses to improve distal outflow and one patient had a femorofemoral bypass graft to restore circulation to the contralateral ischemic extremity. The ankle/brachial indices of all patients significantly improved after the procedure (from a mean of 0.32 to a mean of 0.75) and all grafts are patent to date (mean follow-up 10 months). There were no deaths or limb loss in this group of patients. These favorable results indicate that this minimally invasive approach, which permits a new arterial graft to be inserted through a remote access site, is a valuable method for providing unobstructed arterial inflow after aortoiliofemoral graft failure. This procedure may be particularly valuable when there are contraindications to the use of axillary arteries or the thoracic aorta as alternatives to complex reoperative abdominal aortic surgery.

Aged↗
PubMed1995

Transfemoral endovascular repair of iliac artery aneurysms.

PURPOSE: This report evaluates the application of transfemoral endovascular repair of iliac artery aneurysms. PATIENTS AND METHODS: Over a 20-month period, 11 patients with serious comorbid illnesses and a total of 14 iliac artery aneurysms were treated with endovascular grafts composed of polytetrafluoroethylene conduits combined with balloon expandable iliac artery stents (Palmaz). Nine right common, 3 left common, and 2 right internal iliac artery aneurysms were treated. The patients were men between 58 and 89 years of age (mean 72). Eight patients had isolated aneurysms and 3 had multiple iliac artery aneurysms. RESULTS: Endovascular iliac grafts were successfully placed in all 11 patients. No procedural deaths occurred. Follow-up ranged from 3 to 21 months (mean 11). No acute or late graft thromboses occurred. CONCLUSIONS: Transluminally placed endovascular stented grafts can be used to successfully exclude iliac artery aneurysms from the circulation while maintaining lower-extremity arterial perfusion. However, longer follow-up in more patients is necessary to confirm the durability of this technique.

Aged↗
PubMed1995

Endovascular aortoiliac grafts in combination with standard infrainguinal arterial bypasses in the management of limb-threatening ischemia: preliminary report.

PURPOSE: Occlusive disease of the aortoiliac segment may lead to limb-threatening ischemia, if coexisting disease is present in the femoral, popliteal, or tibial arteries. The combined treatment of severe aortoiliac and infrainguinal disease with standard techniques may be hazardous or contraindicated in patients with multiple previous reconstructions, severe comorbid medical illnesses, or both. This report summarizes the technical feasibility and early results of aortoiliac endovascular stented grafts (ESGs) in combination with conventional surgical reconstructions for the treatment of multilevel arterial occlusive disease. METHODS: Seventeen patients with multilevel aortoiliofemoral limb-threatening occlusive disease had an ESG inserted to treat long-segment occlusive disease followed by a conventional surgical bypass. ESGs originated from the aortoiliac junction (seven) or the common iliac artery (10) and were inserted into the common femoral (nine), superficial femoral (four), or deep femoral (four) artery. ESG lengths ranged from 16 to 30 cm (mean, 21 cm). Conventional surgical bypasses were constructed from polytetrafluoroethylene (15) or saphenous vein (two) and extended to the popliteal (12), tibial (two), or contralateral femoral (three) arteries. RESULTS: Technical success in graft insertion was achieved in 17 (94%) of 18 attempted ESG procedures. The 1-year primary and secondary cumulative patency rates for ESGs were 94% +/- 10% and 100%, respectively, whereas the 1- and 2-year patency rates for the extravascular grafts were 92% +/- 10% and 100%, respectively. Four patients had minor postprocedure complications (23%), and no deaths occurred. One patient lost his limb at 16 months because of severe pedal sepsis. CONCLUSIONS: Transluminally placed stented grafts in combination with conventional surgical infrainguinal bypasses are a technically feasible and potentially safe option for the treatment of limb-threatening aortoiliofemoral occlusive disease and have demonstrated encouraging early patency. Long-term follow-up will be necessary before widespread application of this technique is advocated.

Adult↗
PubMed1995

Human transluminally placed endovascular stented grafts: preliminary histopathologic analysis of healing grafts in aortoiliac and femoral artery occlusive disease.

PURPOSE: The purpose of this study was to perform a preliminary histopathologic analysis of explanted human endovascular stented grafts from patients treated for occlusive disease. METHODS: Over a 16-month period, 26 endovascular stented grafts were placed in 21 patients with limb-threatening ischemia caused by aortoiliac or femoral artery occlusive disease. All grafts were inserted through open arteriotomies remote from the region of primary disease. During the follow-up period, two patients died of preexisting heart disease 2 weeks and 7 months after grafting, and a portion of their endovascular grafts were the surrounding artery was explanted. Specimens from five other endovascular grafts were obtained during surgical revision for graft stenosis after 3 and 6 weeks and for outflow artery stenosis after 3, 5, and 6 months. All specimens were formalin fixed and studied with hematoxylin and eosin and trichrome staining and immunohistochemically for factor VIII-related antigen, alpha actin smooth muscle, macrophage antigen (MAC-387) and PC-10 (a mouse monoclonal antibody which specifically recognizes proliferating cell nuclear antigen in paraffin sections). RESULTS: Three weeks after placement of the stented grafts, organizing thrombus was present on both surfaces of the expanded polytetrafluoroethylene (PTFE) grafts. At 6 weeks, evidence of a neointima with overlying endothelium was seen in the perianastomotic region, and 3 months after grafting it was seen 1 to 3 cm from the anastomosis. The specimen explanted at 5 months demonstrated factor VIII-positive cells 8 cm from the anastomosis. The histopathologic condition of the external capsule appeared to vary, depending on the presence or absence of an external wrap on the PTFE graft and on which layer in the arterial wall the graft was inserted. A foreign body reaction characterized by multinucleated giant cells was seen adjacent to wrapped grafts or around those placed in an intraadventitial plane. Grafts inserted within the media were surrounded by orderly, arranged, smooth muscle cells and few mononuclear cells. Extensive smooth muscle cell proliferation (PC-10 activity) was not seen within native artery atherosclerotic plaques peripherally displaced and external to prosthetic endovascular grafts. CONCLUSIONS: These preliminary observations on the healing of PTFE endovascular stented grafts in human beings demonstrate limited plaque hyperplasia and the presence of endothelial cells on the luminal surface remote from the graft-artery anastomosis. It is unclear whether this is a unique manifestation of healing in prosthetic grafts inserted within the walls of arteries.

Actins↗
PubMed1995

Initial experience with transluminally placed endovascular grafts for the treatment of complex vascular lesions.

OBJECTIVES: Complex arterial occlusive, traumatic, and aneurysmal lesions may be difficult or impossible to treat successfully by standard surgical techniques when severe medical or surgical comorbidities exist. The authors describe a single center's experience over a 2 1/2-year period with 96 endovascular graft procedures performed to treat 100 arterial lesions in 92 patients. PATIENTS AND METHODS: Thirty-three patients had 36 large aortic and/or peripheral artery aneurysms, 48 had 53 multilevel limb-threatening aortoiliac and/or femoropopliteal occlusive lesions, and 11 had traumatic arterial injuries (false aneurysms and arteriovenous fistulas). Endovascular grafts were placed through remote arteriotomies under local (16[17%]), epidural (42[43%]), or general (38[40%]) anesthesia. RESULTS: Technical and clinical successes were achieved in 91% of the patients with aneurysms, 91% with occlusive lesions, and 100% with traumatic arterial lesions. These patients and grafts have been followed from 1 to 30 months (mean, 13 months). The primary and secondary patency rates at 18 months for aortoiliac occlusions were 77% and 95%, respectively. The 18-month limb salvage rate was 98%. Immediately after aortic aneurysm exclusion, a total of 6 (33%) perigraft channels were detected; 3 of these closed within 8 weeks. Endovascular stented graft procedures were associated with a 10% major and a 14% minor complication rate. The overall 30-day mortality rate for this entire series was 6%. CONCLUSIONS: This initial experience with endovascular graft repair of complex arterial lesions justifies further use and careful evaluation of this technique for major arterial reconstruction.

Adolescent↗
PubMed1995

Endovascular repair of abdominal aortic aneurysm: value of postoperative follow-up with helical CT.

OBJECTIVE: Transfemorally placed endoluminal grafts are currently being evaluated as an alternative to open surgery for the treatment of abdominal aortic aneurysms. We determined the value of helical CT for the follow-up of patients treated with this new procedure. The purposes of this study were to determine CT features of a technically successful procedure, detect complications, and compare findings on CT scans obtained 24-48 hr after insertion of the graft with findings on angiograms obtained at the end of the endovascular procedure. SUBJECTS AND METHODS: Seven patients with large abdominal aortic aneurysms had helical CT within 48 hr after transfemoral insertion of an endoluminal graft. Findings on these CT scans were compared with findings on digital completion angiograms obtained immediately after placement of the graft. Additional follow-up CT scans were obtained for up to 15 months (mean, 8 months). The size of the aneurysmal sac; completeness of perigraft thrombosis; and position, shape, and patency of the device were recorded. RESULTS: CT scans obtained 24-48 hr after placement of the grafts showed complete thrombosis of the aneurysmal sac in three patients and incomplete thrombosis with patent perigraft channels in the four remaining patients. Angiograms showed a patent perigraft channel in only one patient. Two of four initially patent channels subsequently closed, but one of them recurred. Of four thrombosed aneurysms, two decreased in size, and two were unchanged on later follow-up. Of three aneurysms associated with perigraft channels, two became enlarged and one was stable. On the basis of CT criteria, successful endovascular repair was shown in four (57%) of seven patients. CONCLUSION: Helical CT is a sensitive means of evaluating the efficacy of endoluminal grafts. Decreased or stable size of the aneurysmal sac without perigraft channels on late follow-up CT signifies technical success. Persistence or recurrence of perigraft channels is the most likely cause of later enlargement of an aneurysm and therefore suggests procedural failure. Helical CT was more sensitive than angiography for detection of perigraft channels that occurred soon after treatment.

Aged↗
PubMed1994

Utility of embolization or chemoembolization as second-line treatment in patients with advanced or recurrent colorectal carcinoma.

BACKGROUND: Second-line therapy of patients with colorectal cancer metastatic to the liver is unsatisfactory. One alternative to systemic treatment is therapy directed locoregionally. METHODS: Twenty-four patients with unresectable colorectal cancer with bulky liver metastases who had failed prior systemic therapy were randomized to treatment with either embolization or chemoembolization. For the embolization group, particulate transcatheter polyvinyl alcohol (PVA) (150-250-microns particles) mixed with full-strength iodinated radiographic contrast was administered under direct fluoroscopic control. In patients randomized to chemoembolization, 5-fluorouracil (750 mg/m2) and recombinant alpha-2a-interferon (Roche Laboratories, Nutley, NJ) (9-MU) were thoroughly mixed into the PVA contrast suspension. Study end points were response to therapy and survival. RESULTS: Of 24 patients, 13 were randomized to chemoembolization and 11 to embolization therapy. All were assessable for toxicity, response, and complications. Among the first 13 patients treated initially, a suppurative abscess developed in one patient, who died. Eleven subsequent patients were pretreated with oral and intravenous antibiotics without further infectious complications. Five patients had hemorrhagic complications, two of which were serious. The treatment was otherwise well tolerated, with most patients experiencing transient pain, fevers, and elevations in leukocyte counts and liver enzymes, which resolved spontaneously. Computed tomography scans of the liver were used to assess patient response to therapy. There were 6 responders (25%) among the 24 patients treated. No differences in response to treatment or survival between the embolization and chemoembolization groups were noted. With a median follow-up of more than 12 months, the median survival was 9.3 months from the time of embolization therapy. CONCLUSIONS: Embolization and chemoembolization therapy appear to have antitumor activity as second-line therapy in patients with colorectal carcinoma with bulky liver metastases. Although generally well tolerated, complications of this therapy may be severe. The addition of further patients to this trial will allow a rigorous comparison of embolization alone versus embolization with chemotherapy.

Adult↗
PubMed1994

Transluminally placed endovascular stented graft repair for arterial trauma.

PURPOSE: Intravascular stents have become important tools for the management of vascular lesions; however, stents in combination with vascular grafts have only recently reached clinical application. This report describes an experience with stented grafts for the treatment of penetrating arterial trauma. METHODS: Seven transluminally placed stented grafts were used to treat one arteriovenous fistula and six pseudoaneurysms. These grafts were successfully inserted percutaneously or through open arteriotomies that were remote from the site of vascular trauma. The devices were composed of balloon-expandable stainless steel stents covered with polytetrafluoroethylene grafts. RESULTS: Patency up to 14 months was achieved (mean follow-up 6.5 months) with these stented grafts. The use of stented grafts appears to be associated with decreased blood loss, a less invasive insertion procedure, reduced requirements for anesthesia, and a limited need for an extensive dissection in the traumatized field. These advantages are particularly important in patients with central arteriovenous fistulas or false aneurysms who are critically ill from other coexisting injuries or medical comorbidities. CONCLUSIONS: The use of stented grafts already appears justified to treat traumatic arterial lesions in critically ill patients. Although the early results with the seven cases in this report are encouraging, documentation of long-term effectiveness must be obtained before these devices can be recommended for widespread or generalized use in the treatment of major arterial injuries.

Adult↗
PubMed1994

Transfemoral endovascular stented graft treatment of aorto-iliac and femoropopliteal occlusive disease for limb salvage.

BACKGROUND: Endovascular stented grafts employ a new technique that blends intravascular stent and prosthetic graft technologies. These devices may be used to treat arterial aneurysms, occlusive disease, and vascular injuries. This report describes the application of stented grafts to the treatment of limb-threatening ischemia secondary to occlusive disease of the aorta, iliac, and femoral arteries. METHODS: Three patients with limb-threatening ischemia and severe comorbid medical illnesses were treated with transvascular stented grafts that were composed of 6-mm thin-walled polytetrafluoroethylene grafts and Palmaz balloon expandable stents. The grafts were inserted through a cutdown in an artery remote from the site of occlusion and introduced into the vascular system within 14-Fr introducer sheaths. RESULTS: Technical success was documented in all three patients with restoration of arterial continuity following stent graft deployment. Patency and limb salvage has been achieved to 1 year. One patient required further dilatation of the proximal stent at 6 weeks. Complications were limited to an iliofemoral deep vein thrombosis in one patient. CONCLUSIONS: Endovascular stented grafts can be inserted to treat limb-threatening ischemia. Although these initial results are encouraging, greater experience in more patients observed for longer periods of time is necessary before this technique can be advocated for widespread use.

Aortic Diseases↗